Health experts had hoped that moving from chewing tobacco and paper products to vaping systems to deliver nicotine would result in advances in health and safety. The thought was that e-cigarettes would be a bridge to quitting other tobacco products and that the decrease in long-term harm would be significant.

A recent report did not find this expectation and hope to have been valid. Electronic cigarettes, which use vapors to deliver nicotine, have gained increasing popularity — particularly among teens and young adults.

Samir Soneji, Ph.D., based at the Dartmouth Institute for Health Policy & Clinical Practice, Geisel School of Medicine, used a simulation model drawing data from census counts, national health and tobacco use surveys as well as available published literature. The technique used calculations of the projected increase or decrease in life span attributed to using e-cigarettes and the transition into long-term smoking for those who had never smoked in a cohort from the U.S. 2014 population.

An estimated 2,070 current smokers would quit smoking and would refrain from smoking for more than seven years based on the model. Sadly, the model predicted that 168,000 adolescents who had never smoked would take up the habit, and an additional 114,000 to 229,000 young adults would take up smoking and eventually become long-term smokers using e-cigarettes.

There was estimated to be 1,510,000 years of lost life associated with the initiated smoking of e-cigarettes.

There is evidence that e-cigarettes can be helpful for quitting other traditional tobacco products and may have lesser harm in some aspects compared to other products. The problem is that e-cigarettes hold an appeal to teenagers and young adults.

Many teens own vaping paraphernalia related to e-cigarettes. It is not just the nicotine that is in e-cigarettes that present harm, but the flavorings that are popular among teenagers and young adults can be carcinogenic.

"Although the tobacco industry markets e-cigarettes as a tool to help adult smokers quit smoking, e-cigarette use actually only marginally increases the number of adult cigarette smokers who are able to successfully quit," Soneji said. "On the other hand, e-cigarettes may facilitate cigarette smoking initiation and confer substantial harm to adolescents and young adults once they are introduced to nicotine."

It is important to recognize that the lost years of life associated with the initiation of e-cigarette smoking currently outweigh the gains in longevity associated with e-cigarettes assisting with smoking cessation. Every effort should be made to educate teenagers and young adults about the consequences of using e-cigarettes.

Never taking up smoking in any form — paper and chewing tobacco or e-cigarettes — is the only means to assure significant gains in longevity.